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fix: display correct exponent in tracker, switch directions, i.e. meaning of exp 0 <-> 128

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qm210
2024-10-22 00:29:09 +02:00
parent 15c1126d11
commit cf05e68471
3 changed files with 28 additions and 27 deletions
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46
vm/compiler/templates/amd64-386/sources.asm
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@ -145,41 +145,41 @@ su_op_envelopexp_statechange:
su_op_envelopexp_applyexp:
fstp st1 ; x', where x' is the new value
; qm120: store the linear envelope in [level] because this is read again for the next value (cf. "envelope")
fst dword [{{.WRK}} + 4] ; [level]=x'
fst dword [{{.WRK}} + 4] ; [level]=x'
; qm210: NOW THE ACTUAL EXPONENTIAL SCALING
; - scale the exponent in [0; 1] to [0.125; 8], call that kappa = 2^(6*(expo-0.5))
fld dword [r10] ; stack: [ expo, x' ]
fld dword [r10] ; stack: [ expo, x' ]
{{.Prepare (.Float 0.5)}}
fld dword [{{.Use (.Float 0.5)}}] ; stack: [ 0.5, expo, x' ]
fsubp st1, st0 ; stack: [ expo-0.5, x' ]
fld dword [{{.Use (.Float 0.5)}}] ; stack: [ 0.5, expo, x' ]
fsubrp st1, st0 ; stack: [ expo-0.5, x' ]
{{.Prepare (.Int 6)}}
fimul dword [{{.Use (.Int 6)}}] ; stack: [ 6*(expo-0.5), x' ]
{{.Call "su_power"}} ; stack: [ kappa, x' ]
fxch st1 ; stack: [ x', kappa ]
fimul dword [{{.Use (.Int 6)}}] ; stack: [ 6*(expo-0.5), x' ]
{{.Call "su_power"}} ; stack: [ kappa, x' ]
fxch st1 ; stack: [ x', kappa ]
; - now we need (x')^(kappa), but care for x' == 0 first
fldz ; stack: [ 0, x', kappa ]
fucomip st1 ; stack [ x', kappa ] and ZF = (x' == 0)
jz su_op_envelopexp_avoid_zero_glitch
fldz ; stack: [ 0, x', kappa ]
fucomip st1 ; stack [ x', kappa ] and ZF = (x' == 0)
jz su_op_envelopexp_avoid_zero_glitch
; - still around? calculate the actual x'' = x^kappa then
fyl2x ; stack: [ kappa * log2 x' ]
{{.Call "su_power"}} ; stack: [ x ^ kappa ]
jmp short su_op_envelopexp_applybaseline
fyl2x ; stack: [ kappa * log2 x' ]
{{.Call "su_power"}} ; stack: [ x ^ kappa ]
jmp short su_op_envelopexp_applybaseline
su_op_envelopexp_avoid_zero_glitch:
fstp st1
fstp st1
su_op_envelopexp_applybaseline:
; - and scale the result to a different baseline: x''' = (B + (1 - B) * x'') for B != 0 (check not required)
fld dword [{{.WRK}} + 12] ; stack: [ B, x'' ]
fld1 ; stack: [ 1, B, x'' ]
fsub st0, st1 ; stack: [ 1-B, B, x'' ]
fmulp st2, st0 ; stack: [ (1-B) * x'', B ]
faddp st1, st0 ; stack: [ (1-B) * x'' + B ]
jmp short su_op_envelopexp_leave
fld dword [{{.WRK}} + 12] ; stack: [ B, x'' ]
fld1 ; stack: [ 1, B, x'' ]
fsub st0, st1 ; stack: [ 1-B, B, x'' ]
fmulp st2, st0 ; stack: [ (1-B) * x'', B ]
faddp st1, st0 ; stack: [ (1-B) * x'' + B ]
jmp short su_op_envelopexp_leave
su_op_envelopexp_sustain:
; qm210: overwrite level, because else the release cannot work
fld dword [{{.Input "envelopexp" "sustain"}}]
fld dword [{{.Input "envelopexp" "sustain"}}]
su_op_envelopexp_skipexp:
fst dword [{{.WRK}} + 4]
fstp st1
fst dword [{{.WRK}} + 4]
fstp st1
su_op_envelopexp_leave:
; qm210: scaling because I use my wave editor as a function plotter ;)
fmul dword [{{.Input "envelopexp" "gain"}}] ; [gain]*x''